rear diff cover leak
- Thread starter 84venom
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It's a gasket. I wouldn't go with something not recommended by Ford.
The diff cover will come off. You may need to remove the suspension parts behind the diff. The diff fluid drain will make a mess so you should have a big pan to catch it. You have to clean it all up and install a new gasket. It may still drip even then.
I say that most times that a little drip is not a problem. I use an old cardboard piece on the floor to catch a drip (my old Mustang and Porsche drip a little fluid).
Diff= No problem.
Transmission = No problem.
Rear main seal = Problem. It will leak down on the clutch and destroy it.
The diff cover will come off. You may need to remove the suspension parts behind the diff. The diff fluid drain will make a mess so you should have a big pan to catch it. You have to clean it all up and install a new gasket. It may still drip even then.
I say that most times that a little drip is not a problem. I use an old cardboard piece on the floor to catch a drip (my old Mustang and Porsche drip a little fluid).
Diff= No problem.
Transmission = No problem.
Rear main seal = Problem. It will leak down on the clutch and destroy it.
I replaced the cover in my car so I would avoid this problem... I ended up doing the Ford Racing cover since they are 10x stronger than the standard factory covers. It took me just about an hour to do the swap. It is a tight job but it is doable. Svtguy is on point with his post.
I wish you would service my cars.
It takes me an hour to just jack the car up and level it up with jack stands.
Then I have to remove the diff bolts (some are hard to get to). Drain the fluids. Then scrape off the old gasket. I need to clean the surfaces. Then very carefully torque the bolts down to specs with the new gasket.
I need to pump the fresh fluid back in the diff. Then lower the car back down. You can do this in one hour? :-D
Just use a good quality RTV only. The cover has a recessed groove in it for the RTV. Clean the old RTV out of the groove in the cover, off of the diff housing and out of the bolt holes in the diff housing. Once all the old RTV is removed, I use some spray brake clean on a rag and wipe both surfaces to get any oil off. Once the cover is reinstalled, torque all the cover bolts. I let the RTV setup overnight before I install the gear oil.
Good Luck.
Paul.
I've never used the additive- is that something I should start using?
Gaskets are always better, unless you have 4-wheel drive mud truck, and you're under water for fun. RTV has its purpose when used sparingly, but RTV gets in the bolt holes, harder to clean off, squishes into the inside(if too much is installed), etc. Just to many negatives for me. I always use a little (very thin) coating "Aviation Permatex" on my differential tin cover gaskets. If you're using an aluminum replacement cover, you don't need anything but a gasket. You have two hard surfaces. I never use anything on 9" Ford diffs. gaskets either.
In my 50+ years of being a mech., I've never had a gasket leak, when installed properly on a clean level flat surface.
In my 50+ years of being a mech., I've never had a gasket leak, when installed properly on a clean level flat surface.
I'm not disagreeing with you about gaskets or excessive use of RTV during assembly, but in this case, the 00R's rear diff cover has a rear support mount bolted to it also. My thinking is that if a gasket is installed between the cover and the diff it could allow the cover to shift on the diff when the car accelerates/decelerates. This could wear the gasket causing a leak. With just RTV in the covers groove, the aluminum cover is bolted directly to the aluminum diff.
Just my opinion.
Paul.
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Get Permatex Right Stuff RTV. Clean the surfaces with brake cleaner as mentioned before and then spread a thin coat of the right stuff on the differential surface. Torque the cover to spec. I have never had a leak when installed this way. The right stuff cures very fast and is ready to drive immediately. It is pretty easy to remove once dried too. Can't go wrong.
That is a point well taken, and could possibly be an exception to my rule.
I'm not opposed to other ideas that apply to unique applications, 4X4's, '00 Cobra "R"s, submarine's, etc.
'Adding' a gasket makes the diff housing/cover assembly a tad longer and can in some cases make it a little more difficult to reinstall. I don't like using a gasket. I like cleaning the surfaces very well and use the gray Ford Motorcraft TA-29 silicone sealant.
The reason the diff cover leaks is because the differential housing is not stabilized in the OEM rubber mounts. At the absolute minimum you want to get some front and rear diff mount bushings and some of us that went through this more than 10 years ago have already figured out the IRS and what needs to be done to it. As a matter of fact I've developed a complete line of parts to fix the Cobra IRS. You can check the site out here:
http://fulltiltboogieracing.com/
For more information regarding the IRS you might want to check out the FAQ on our site:
http://fulltiltboogieracing.com/faqs.htm
Obviously the Ford Racing cover is the ultimate fix as the egg shell thin OEM cover has proven it's weakness thousands of times in the past. All of these goodies and more can be found on the COBRA IRS order page on our site:
http://fulltiltboogieracing.com/1999-2004_Cobra_Suspension_Parts_and_Tools.htm
I'd be happy to answer any questions you might have.
:thumbsup: :coolman: :beer:
I'm in the process of removing the rear diff cover on mine (my slow leak began about a month ago) and, once I had removed all the bolts, realized that I may not have enough room to actually get it off without removing some suspension parts, etc. Can anyone that has successfully removed the cover advise me on: A) what, if anything, additional do I need to remove and/or loosen, and B) if not, give me a tip on how to best to get the cover off. Thanks in advance.
If you remove the driveshaft and all of the differential attaching hardware you can push the diff housing forward enough to be able to get the OEM cover off to reseal it. That's only with the OEM cover. The Ford Racing cover is too beefy to do that.
FWIW
I got the cover off and went back with RTV. Anyone know the correct amount of fluid to put back in? I'm planning on supplementing it with 4 oz of the Friction Modifier. Thanks.
The diff will take just under a quart and a half. If you're still on the OEM clutched diff put in the friction modifier first. Fill to the bottom of the fill hole or until the fluid runs out.
Couple more things. Let the sealant cure for 24 hours before filling and wait 48 hours to drive.
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